1. Field of the Invention.
The present invention relates to a flushing device that includes an integrally formed flushing luer connected to a forming tube that is used with a "rapid exchange" or "monorail" balloon catheter. The flushing device can be friction fit over a distal end portion of the balloon catheter and is used to flush an inner or guidewire receiving lumen in the distal end of the "rapid exchange" or "monorail" catheter prior to inserting the catheter into a patient.
2. Description of the related art including information disclosed under 37 CFR .sctn..sctn.1.97-1.99.
"Rapid exchange" or "monorail" balloon catheters are well known in the art of balloon catheters. Such catheters include a distal end portion which has an outer lumen for carrying fluid to a balloon at the distal end portion of the catheter for inflating the balloon and an inner or guidewire receiving lumen for advancing the catheter over a guidewire. The balloon is inflated by forcing fluid into the outer lumen, via a port at a proximal end of the catheter, and into the balloon.
A guidewire previously inserted into a blood vessel in a person's body is placed into the inner or guidewire receiving lumen in the catheter. The guidewire receiving lumen in the catheter has a distal opening at a distal end of the catheter and a proximal opening located proximally of the distal opening at a cut away portion of the catheter.
The guidewire receiving lumen in the catheter extends along the distal end portion of the catheter only, unlike the outer lumen in the catheter which extends all the way from a proximal end of the catheter to the balloon at the distal end portion of the catheter.
The "rapid exchange" or "monorail" catheter is placed over a guidewire by placing a proximal end of the guidewire into the distal opening of the inner or guidewire receiving lumen and then pushing the catheter over the guidewire. The guidewire exits the guidewire receiving lumen of the catheter at the proximally located opening.
Before placing the catheter over the guidewire, it is desirable to flush the guidewire lumen with a flushing solution, generally a saline solution, to eliminate contaminants in the guidewire receiving lumen and/or to provide a lubricant so that the catheter can be slid over the guidewire more easily.
Heretofore, a blunt needle connected to a syringe has been used to flush the guidewire receiving lumen of "rapid exchange" or "monorail" balloon catheters. A person inserts the blunt needle, into the distal opening of the guidewire receiving lumen and then forces flushing fluid from the syringe, through the needle, and into and through the inner or guidewire receiving lumen of the catheter.
However, using a needle and syringe can be cumbersome, dangerous and costly because the needle can puncture the balloon or the catheter, rendering the balloon catheter inoperable.
As will be described below in greater detail, the flushing device of the present invention solves these problems associated with using a syringe and needle for flushing the guidewire receiving lumen of the catheter.
Heretofore, at least one device has been proposed for flushing the guidewire receiving lumen of a catheter. The device is disclosed in the following U.S. Patent:
______________________________________ U.S. Pat. No. Patentee ______________________________________ 5,372,592 Gambale ______________________________________
The Gambale U.S. Patent No. discloses a flushing tool and method for safely flushing or lubricating a guidewire lumen of a catheter. A luer fitting is secured to a proximal end of an elongate member, such as a hypodermic needle, and is in flow through communication with the elongate member. The distal end of the elongate member is inserted into the guidewire lumen of the catheter and a clip extending from the luer is attached to the catheter shaft or to a container which stores the catheter. Flushing or lubricating solution can be injected through the luer and elongate member and through the guidewire lumen.